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Following installation this line strainer must be cleaned and replaced. This needs to be carried out on a regular basis as part
of the annual maintenance/service check.
Safety
The immersion heaters are indirectly supplied power via the main boiler terminal block which must be earthed. The main
power supply to the boiler must be isolated from the mains before the cover is removed on every occasion.
Replacement immersion heaters should be obtained from Elnur UK Ltd.
Important
Failure to follow the drain down procedure will invalidate the warranty.
NEVER drain the cylinder of hot water and then close all cylinder inlets and outlets
REASON: As the air remaining in the cylinder cools the pressure inside the cylinder will fall below atmospheric and cause
damage to the cylinder.
NEVER close the cold main and drain the cylinder via any tap connected to it.
REASON: As the air remaining in the cylinder cools the pressure inside the cylinder will fall below atmospheric and cause
damage to the cylinder.
Fitting Blending Valves (thermostatic mixing valves) To the Gabarrón Mattira combi boiler
When fitting a blending valve to the unvented appliances, it is important that the installation does not contravene the
G3, WRC and Health and Safety directives or the manufacturer’s recommendations. If this is the case, then the warranty
should be null & void. The key requirements to comply with these regulations are:
1. Any fitting or material in contact with potable water (e.g. a blending valve) must be approved by WRC or an equivalent
body.
2. Connections or wiring arrangements must not bypass any safety devices.
3. Any expansion due to heating must not be allowed to expand back into the cold mains.
4. The settings of any safety devices must not be tampered with or adjusted.
4.7 TYPICAL INSTALLATION LAYOUT shows the cold water port of the blending valve connected to the balanced cold
water outlet. This arrangement will only be acceptable if a WRAS approved non-return valve is fitted, otherwise, during the
heating cycle, the water will expand back into the mains supply, as the regulating valve must not be relied upon to act as a
check valve under all operating conditions.
Depending upon the characteristics of the blending valve, hot water may also flow from the balanced cold water taps.
It is not permitted for the cold water port of the blending valve to be connected to the mains cold water supply before the
inlet control group. This arrangement is completely unacceptable and illegal because the water is allowed to expand in to
mains cold water supply, the vessel will be charged to the incoming mains supply which may be considerably higher than the
working pressure of the vessel.
Installation Checks
Check the pressure on the air side of the expansion vessel = 3 bar. This must be done when the water in the cylinder is free
to expand in atmospheric pressure or the cylinder and relevant pipe work is empty.
Check that the drain cock is closed, and open all the cold and hot water taps and other terminal fittings. Allow the system to
fill with water, and to run until there is no air left in the system. Close the taps and inspect the system closely for leaks.
Manually open the Relief Valves one by one and check that water is discharged and run freely through the tundish and out at
the discharge point. The pipework should accept full bore discharge without overflowing at the tundish, and the valve should
seat satisfactorily.
In line with good plumbing practice, use with excessive flux should be avoided. When soldering close to the boiler, ensure
flux/solder does not contaminate the cylinder inside, since this can cause corrosion. Flushing should be done performed as
per BS EN 806:4 2010 section 6.2.
Allow the cylinder to heat to normal working temperature, then thoroughly flush the domestic hot and cold water pipework
through each tap.
